Metal clusters abstraction reaction

Metal cluster complexes containing vinylidene ligands have been considered as models of species present when olefins or alkynes are chemisorbed on metal surfaces (114). Vinylidene has been detected in reactions of ethylene or acetylene with Fe(100), Ni( 111), and Pt(l 11) surfaces (115), and was shown to be an intermediate by theoretical studies on a manganese surface (116). The facile cleavage of C-H bonds which occurs in these systems, together with hydrogen addition or abstraction, also occurs on metal clusters. Typical of the reactions considered is the hydrogen transfer reaction... 

Abstraction, reductive coupling, electron transfer, bond activation, oxidative addition, n-complexation, disproportionation and metal cluster formation are some of the reactions that occur when metal atoms interact with organic polymers and small molecules. Examples of these reactions are provided from the literature on the organometallic chemistry of free atoms and coordination-deficient molecules. Past uses of model compound studies to understand the early stages of chromium metallization on polyimide are critiqued. New evidence for reactions of chromium atoms with compounds related to polyimides is given. 

This is the first example of an abstraction reaction of a metal cluster system. ... 

Assuming a maximum spin for the cation leads to five uncoupled, or weakly coupled electrons likely to yield the observed product Nb8Ci2 (I)5. The termination of the reaction of VgCn at four adducts is more difficult to interpret because the electronic configuration of the metal is similar to that of niobium. It is possible that stronger localization of the metal electrons on the inner tetrahedron makes those electrons less accessible for the abstraction reaction. That yields the following electron distribution for the neutral cluster ... 

ABSTRACT. Interactions of organometallic compounds with metal surfaces can be used to produce metal films and coatings as well as to modify the properties of metal catalysts for hydrocarbon conversion. The literature is reviewed, and results are evaluated characterizing the interaction of metal carbonyl clusters with surfaces of supported metals under mild conditions. The reactions lead to the preparation of highly dispersed bimetallic particles, which have homogeneous compositions and nonadditive properties in CO hydrogenation and hydrocarbon conversion. 

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